I was a ceramics major for a couple of years, so I may be of assistance with the kiln.

1) The lid is probably happy staying on with friction and gravity. Unless there's a gigantic crack, it shouldn't affect the firing temperature. Worst-case, if the lid gets knocked off, you're likely to get shattered clay from sudden cooling.

2) You measure the temperature of a kiln with "pyrometric cones" -- small triangular pieces of clay that have been formulated to melt at a specific temperature. You position the cone by the peephole, and when the cone sags, you know you have arrived at the right temperature.http://en.wikipedia.org/wiki/Pyrometric_cone

Dont have a pallet jack, but do have a rolling 2 ton engine hoist. have to check height of the pickle to see if I can lift it (may be too tall for the hoist). If I can then it should move pretty easily.